User:Mbennie/Notebook/Papers and Books/IgA Autotransporter

1. Veiga E, de Lorenzo V, and Fernández LA. Autotransporters as scaffolds for novel bacterial adhesins: surface properties of Escherichia coli cells displaying Jun/Fos dimerization domains. J Bacteriol. 2003 Sep;185(18):5585-90. DOI:10.1128/JB.185.18.5585-5590.2003 |

• Fused leucine zipper with autotransporter creating a protein that was expressed on the cell surface and adhered to a similar protein expressed in another population of cells, causing the cells to clump out of solution
• Used IgA as the AT
• Used Fos and Jun as the leucine zippers
• Used an E-tag to test whether the protein was expressed on the surface (using an antibody)
• Used pelB "for an efficient secretion"
• Membrane remains stable

2. Klauser T, Krämer J, Otzelberger K, Pohlner J, and Meyer TF. Characterization of the Neisseria Iga beta-core. The essential unit for outer membrane targeting and extracellular protein secretion. J Mol Biol. 1993 Dec 5;234(3):579-93. DOI:10.1006/jmbi.1993.1613 |

• Concludes a subset of IgA (882 bp) can transport and display a passenger protein by itself, called Iga beta-core
• Figured out that Iga beta was enough, then kept cutting up the protein was no longer functional
• This 227aa protein is very well conserved among Neisseria and Haemophilus
• p. 583 - protein sequence of Iga beta-core
• Suggests that cell express 50,000-100,000 copies
• Iga beta-core is "structurally reminiscent of integral outer membrane proteins (OMPs)"
• Suggests further that forty of the amino acids might not be needed (p. 590)
• "Resembles a typical outer membrane protein with a few additional features"

3. Valls M, Atrian S, de Lorenzo V, and Fernández LA. Engineering a mouse metallothionein on the cell surface of Ralstonia eutropha CH34 for immobilization of heavy metals in soil. Nat Biotechnol. 2000 Jun;18(6):661-5. DOI:10.1038/76516 |

• Describes method of bioremediation using r. eutropha using metallothionein (MT) expressed on the cellular surface using IgA beta
• MT binds heavy metal atoms
• Bioaccumulates about 5% of Cd2+ ions tested, but affects the growth of plants in contaminated soil much more (70%)

4. Klauser T, Pohlner J, and Meyer TF. Extracellular transport of cholera toxin B subunit using Neisseria IgA protease beta-domain: conformation-dependent outer membrane translocation. EMBO J. 1990 Jun;9(6):1991-9. DOI:10.1002/j.1460-2075.1990.tb08327.x |

• Discovery that IgA beta contains the ability to display surface proteins by itself
• Observation that there is a highly conserved region within IgA beta, called IgA beta-core, which is the portion that facilitates outer membrane transport
• Observed that disulphide-dependent folding can cause problems in surface display (protein stuck in periplasm)

5. Pohlner J, Halter R, Beyreuther K, and Meyer TF. Gene structure and extracellular secretion of Neisseria gonorrhoeae IgA protease. Nature. 1987 Jan 29-Feb 4;325(6103):458-62. DOI:10.1038/325458a0 |

• A basic description of IgA protein in Neisseria gonorrhoeae

6. Veiga E, de Lorenzo V, and Fernández LA. Probing secretion and translocation of a beta-autotransporter using a reporter single-chain Fv as a cognate passenger domain. Mol Microbiol. 1999 Sep;33(6):1232-43. DOI:10.1046/j.1365-2958.1999.01571.x |

• It is possible to have disulfide-dependent folding, but it decreases efficiency (3-fold with Fv)

7. Oomen CJ, van Ulsen P, van Gelder P, Feijen M, Tommassen J, and Gros P. Structure of the translocator domain of a bacterial autotransporter. EMBO J. 2004 Mar 24;23(6):1257-66. DOI:10.1038/sj.emboj.7600148 |

• Resolves crystal structure of N. meningitidis IgA (highly homologous to N. gonorrhoeae IgA)
• "12-stranded beta-barrel with a hydrophilic pore of 10*12.5 A that is filled by an N-terminus alpha-helix"
• Evidence supporting passenger-domain transport, evidence against oligomer of translocater domains
• Alpha-helix has many interactions with interior of hydrophilic barrel: seven salt bridges, sixteen hydrogen bonds, and numerous van der Waals contacts
• Deletion of alpha-helix results in much lower expression of the protein, but increased pore activity